package com.david.disshappserver.utils;

import java.lang.reflect.Type;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import java.util.Map;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.JsonDeserializationContext;
import com.google.gson.JsonDeserializer;
import com.google.gson.JsonElement;
import com.google.gson.JsonParseException;
import com.google.gson.JsonPrimitive;
import com.google.gson.JsonSerializationContext;
import com.google.gson.JsonSerializer;
import com.google.gson.reflect.TypeToken;

/**
 * json 简单操作的工具类
 */
public class JsonUtils {

    private static Gson gson = null;

    static {
        if (gson == null) {
            gson = new Gson();
        }
    }

    private JsonUtils() {
    }

    /**
     * 将对象转换成json格式
     *
     * @param ts
     * @return
     */
    public static String objectToJson(Object ts) {
        String jsonStr = null;
        if (gson != null) {
            jsonStr = gson.toJson(ts);
        }
        return jsonStr;
    }

    /**
     * 将对象转换成json格式(并自定义日期格式)
     *
     * @param ts
     * @return
     */
    public static String objectToJsonDateSerializer(Object ts, final String dateformat) {
        String jsonStr = null;
        gson = new GsonBuilder().registerTypeHierarchyAdapter(Date.class, new JsonSerializer<Date>() {
            public JsonElement serialize(Date src, Type typeOfSrc,
                                         JsonSerializationContext context) {
                SimpleDateFormat format = new SimpleDateFormat(dateformat);
                return new JsonPrimitive(format.format(src));
            }
        }).setDateFormat(dateformat).create();
        if (gson != null) {
            jsonStr = gson.toJson(ts);
        }
        return jsonStr;
    }

    /**
     * 将json格式转换成list对象
     */
    public static List<?> jsonToList(String jsonStr) {
        List<?> objList = null;
        if (gson != null) {
            Type type = new TypeToken<List<?>>() {
            }.getType();
            objList = gson.fromJson(jsonStr, type);
        }
        return objList;
    }

    /**
     * @param @param  jsonStr
     * @param @param  type
     * @param @return
     * @return List<T>
     * @throws
     * @Title: jsonToList
     * @Description: 将Json转为对应的List
     */
    public static <T> List<T> jsonToList(String jsonStr, Class<T> type) {
        Type listType = new TypeToken<ArrayList<T>>() {
        }.getType();
        List<T> list = null;
        if (gson != null) {
            list = gson.fromJson(jsonStr, listType);
        }
        return list;
    }

    /**
     * 将json格式转换成map对象
     *
     * @param jsonStr
     * @return
     */
    public static Map<?, ?> jsonToMap(String jsonStr) {
        Map<?, ?> objMap = null;
        if (gson != null) {
            Type type = new TypeToken<Map<?, ?>>() {
            }.getType();
            objMap = gson.fromJson(jsonStr, type);
        }
        return objMap;
    }

    /**
     * 将json转换成bean对象
     *
     * @param jsonStr
     * @return
     */
    public static Object jsonToBean(String jsonStr, Class<?> cl) {
        Object obj = null;
        if (gson != null) {
            //jsonStr=jsonStr.replace("\\", "");//去掉'/'
            jsonStr = jsonStr.substring(jsonStr.indexOf("{"), jsonStr.length()); //去掉头尾引号。
            //System.out.println("json串= "+jsonStr);
            obj = gson.fromJson(jsonStr, cl);
        }
        return obj;
    }

    /**
     * 将json转换成bean对象
     *
     * @param jsonStr
     * @param cl
     * @return
     */
    @SuppressWarnings("unchecked")
    public static <T> T jsonToBeanDateSerializer(String jsonStr, Class<T> cl, final String pattern) {
        Object obj = null;
        gson = new GsonBuilder().registerTypeAdapter(Date.class, new JsonDeserializer<Date>() {
            public Date deserialize(JsonElement json, Type typeOfT,
                                    JsonDeserializationContext context)
                    throws JsonParseException {
                SimpleDateFormat format = new SimpleDateFormat(pattern);
                String dateStr = json.getAsString();
                try {
                    return format.parse(dateStr);
                } catch (ParseException e) {
                    e.printStackTrace();
                }
                return null;
            }
        }).setDateFormat(pattern).create();
        if (gson != null) {
            obj = gson.fromJson(jsonStr, cl);
        }
        return (T) obj;
    }

    /**
     * 根据
     *
     * @param jsonStr
     * @param key
     * @return
     */
    public static Object getJsonValue(String jsonStr, String key) {
        Object rulsObj = null;
        Map<?, ?> rulsMap = jsonToMap(jsonStr);
        if (rulsMap != null && rulsMap.size() > 0) {
            rulsObj = rulsMap.get(key);
        }
        return rulsObj;
    }

}